HPC Engineer

NexGen Cloud; Greater London; Hybrid; GBP 85,000 - 110,000; Full time

Benefits offered by this job

Salary + Bonus

Private Medical Insurance

Enhanced Pension Scheme

Flexible working (remote or hybrid)

Ownership & autonomy

Career progression

Collaborative culture

Impact at scale and shaping the team

Job summary

NexGen Cloud is scaling its GPU-based HPC infrastructure in the UK, delivering high-performance AI and compute workloads from London. We seek an HPC Engineer who will own validation, tuning, and day-to-day operation of large NVIDIA GPU clusters, including InfiniBand networks and storage for production workloads.

You will collaborate with architects, network and validation teams, and OEMs to resolve faults, optimize performance and automate repeatable validation across GPU platforms.

Qualifications

• Hands-on experience operating NVIDIA GPU infrastructure at scale, incl. drivers, CUDA, DCGM and diagnosing GPU faults.
• Proven experience running production HPC clusters with a workload manager such as Slurm.
• Strong InfiniBand experience, including subnet management, RDMA, fabric monitoring and fault-finding.
• Experience benchmarking and tuning performance for distributed workloads using NCCL tests, HPL or similar.
• Strong Linux systems administration skills, including OS networking, storage, automation and Git workflows.

Responsibilities

• Own cluster validation before handover: run burn-in, health checks and NCCL/HPL benchmarks against acceptance criteria and resolve underperformance.
• Collaborate with Deployment Solution Architects, Network Engineers, Validation and Support teams, and with NVIDIA and OEMs on hardware faults and RMAs.
• Run production HPC clusters daily, including Slurm, GPU drivers, CUDA, InfiniBand fabrics, subnet management, monitoring and storage integration.
• Tune clusters for AI training and HPC workloads: NCCL settings, GPUDirect RDMA and topology-aware scheduling.
• Build GPU, fabric and job-level monitoring to catch faults early and lead incident response from Xid errors to root cause.
• Automate provisioning, configuration and validation with IaC and repeatable validation suites for each GPU platform.
• Turn incident learnings into automated checks, runbooks and docs to feed production design decisions.

Skills

NVIDIA GPU infra

Slurm HPC

InfiniBand RDMA

NCCL/HPL benchmarks

Linux admin & automation

Tools

GPU drivers

CUDA stack

Job description

NexGen Cloud is a fast-growing GPU cloud and AI infrastructure business. We're the company behind Hyperstack - a self-serve, on-demand cloud platform built for high-performance AI, HPC, and compute-heavy workloads. Powered by 100% renewable energy and NVIDIA architecture, Hyperstack gives teams from AI startups to enterprise the compute they need, without the cost or complexity of legacy cloud.

We move fast, solve hard problems, and build things that matter. If you want ownership, real impact, and a front-row seat to one of the most consequential infrastructure shifts of the decade - this is the place.

THE ROLE: HPC ENGINEER

We're deploying more and more large-scale NVIDIA GPU clusters connected by InfiniBand, and the gap between a cluster that's built and one that delivers its expected training performance is where customer experience is won or lost. We're hiring an HPC Engineer to close that gap: validating and tuning clusters before handover, then owning the HPC layer in production.

This is a role for someone who follows a problem across GPUs, fabric, storage and software until it's fixed rather than handing it off, who won't sign off a cluster that isn't ready, and who's comfortable operating without heavy oversight in a fast-moving environment. It's a permanent, remote role based in the UK, with an on-call rota and occasional travel to data centre sites.

WHAT YOU'LL BE DOING

Rather than a checklist, here's what success in this role actually looks like:

• Own cluster validation before handover: running burn-in, health checks and NCCL, HPL and storage benchmarks against agreed acceptance criteria, and resolving underperformance before it reaches the customer
• Collaborate closely with Deployment Solution Architects, Network Engineers, Validation and Support teams, and with NVIDIA and OEMs on hardware faults and RMAs
• Run production HPC clusters day to day, including Slurm, GPU drivers and the CUDA stack, InfiniBand fabrics (subnet management, monitoring, firmware) and the parallel storage clusters depend on
• Tune clusters for AI training and HPC workloads, from NCCL settings and GPUDirect RDMA to topology-aware scheduling and storage throughput
• Build GPU, fabric and job-level monitoring that catches faults before customers notice, and lead incident response from Xid errors and fabric degradation through to root cause
• Automate provisioning, configuration and validation with infrastructure-as-code, creating a standard, repeatable validation suite for each GPU platform and fabric type
• Turn incident learning into automated checks, runbooks and documentation others can follow, and feed what you learn in production back into how clusters are designed and deployed

ABOUT YOU

We care more about how you think and work than a perfect CV. You'll likely bring a combination of the following:

• Hands-on experience operating NVIDIA GPU infrastructure at scale, including drivers, CUDA, DCGM and diagnosing GPU hardware faults
• Proven experience running production HPC clusters with a workload manager such as Slurm
• Strong practical InfiniBand experience, including subnet management, RDMA, fabric monitoring and fault-finding
• Experience benchmarking and tuning performance for distributed workloads using NCCL tests, HPL or similar
• Strong Linux systems administration skills, including OS-level networking and storage, plus infrastructure automation and Git-based workflows

Nice to Have:

• Experience with large NVIDIA platforms such as HGX H100/H200/B200 or GB200 rack-scale systems, NVIDIA UFM and GPUDirect RDMA
• Parallel file systems such as WEKA, VAST, DDN/Lustre or GPFS
• Running GPU workloads on Kubernetes, or integrating HPC clusters with Kubernetes or OpenStack
• A background supporting AI/ML training, MPI-based HPC applications or research computing, or contributions to open-source HPC projects

WHAT WE OFFER

• Competitive salary and annual discretionary bonus scheme
• Private Medical Insurance
• Enhanced Pension Scheme
• Flexible working arrangements (remote or hybrid, depending on role and location)
• Real ownership and autonomy - the trust to take initiative and experiment
• Visible, meaningful impact as we scale
• Clear career progression in a high-growth company
• A collaborative, international culture built on trust, transparency, and ownership
• The chance to help shape NexGen Cloud's team, culture, and future

WHY APPLY

We welcome applications from all backgrounds. If you enjoy solving complex infrastructure problems and want to build something meaningful at scale, we'd like to hear from you.

MORE INFORMATION

Visit our careers page to learn more about us or follow us on LinkedIn and X to learn more about our journey and keep up with our latest news and releases.

This role is based in London with a hybrid working arrangement.